Works perfectly and I think I love it but unfortunately it requires private windows access "due to a Firefox update" and I am not sure I like it. So I give it 4 stars instead of 5 for the private access thing.

Works, but it is not as easy as other ones, but works...

Very simple and just works by enabling disabling Firefox proxy settings. There is one small issue though, proxy switches on automatically when browser restarts even if it was disabled.

Ben: did you follow the directions in the add-on description

Me: Yes, I did try that, still it turns on (the button becomes green) after restart. I would expected it remember the last state and restore on restart.

I agree with @15016291. When using a proxy software like Shadowsocks in Global Mode, I can't just click the "Turn off proxy" button to stop my browser connecting to the proxy server.

Works as said. Would be great if it switched between Off/On and not System/Manual, or if it gave an option to choose the two states.